For incoming calls, UPC Austria seems to supply the caller's number in local format (i.e. without the country code), for instance "01xxxxxxx" for Vienna, instead of 00431xxxxxxx.

ADAT fails to find the corresponding number in Outlook contacts, and I assume it fails because we store numbers in international format, like +431xxxxxxx.

If you can confirm that the format is the reason, what it best practice to solve it?
I did not find an option in ADAT to make it more clever here.
Can I tell Operator to add the missing country code to the callers number only in case that number starts with a singe zero?

(I cannot cut the first digit and replace it by +43, as this would break international numbers.)

EDIT: ADAT does not seem to recognize the caller even if I store the number in local format in Outlook.
So the problem seems to be ADAT. It only shows the names associated with the internal extensions (which are not even in Outlook!).
But Outlook contacts do work for doing outgoing calls.

Any ideas?
Or is it better to use a commercial tool like Estos for instance?

I ask in the ADAT forum. (I just thought anyone here might have an idea, since the tool is linked on the Kerio website.)

@the other thing:

No, it is regarding incoming calls.
The number of the caller, as we see it when a call comes in.
If it is a foreign caller, we see 004989xxxxxxx... (example Munich in Germany)
If it is a call from within Austria, we see 01xxxxxxx... (example Vienna)

I would have expected that all numbers are given in a uniform format, which can only be the international one, I supposed. So I had expected to see 00431xxxxxxx.

However, obviously, the local format is easier to read for a human on the phone display - so I like it, but I am not sure whether it is technically wise?

I am new to SIP, so maybe this is something common anyway. What is your opinion?

I agree with you that the behavior is not technically wise. As far as I know, only Austrian and German providers do that. They send local numbers in a short format, the rest of the world seems to use the international format either with 00 or +.

I have never used ADAT, but I recall seeing on their wiki, that they do support some number rewriting using regular expressions. If the rewriting also applies to inbound calls then you should be able to modify the numbers.

I don't know of any feature on the Operator side to help you with the matter.

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